layer 3

1. 2G layer 3 Messages
Sys info type
1
(Idle)
Channel number
BCCH that broadcast this
info to MSs
Channels
Hopping channels
RACH control parameters
1) Max retransmission:
MS can send maximum
Channel Request = Max
retransmission+1.
2) Tx-integer:The
interval between
retransmission is a
random value uniformly
select form the
following set
{S,S+1,…S+Tx-
integer-1}.
3) Cell barredAccess:
prevent MS to camp on
this cell in Idle mode
(cell
selection/Reselection).
4) Call reestablishment:
allow MS send RACH
to resume the
connection after call
dropped
Sys info type
2
(Idle)
BCCH Allocation List
MS will get the ARFCH of
BCCH of surrounding cell it
has to measure and decode in
idle mode from this
messages .
• MS will not scan,synch or
decode any
frequencies that are not in
this list
• in Type 2 it will send the
list of the same
band of the serving cell,
BCCH allocation
list of different band will be
sent in Type
2ter.
• In type 2ter also contain the
information

2. about how many neighbors
from different
band mobiles have to add in
the measurement report.
NCC permitted
MS will use this value when
it first enter to
dedicated mode before it get
new information on SACCH.
Sys info type
3
(Idle)
Cell info
MCC & MNC & LAC
Control channel
1) ATT IMSI
attach/detach flag
2) BS-AG-BLKS-RES
number of block
reserve for access grant,
use in the calculation of
paging group.
3) CCCH-CONF indicate
whether CCCH is
combined with
SDCCH.
4) BS-PA-MFRMS
Multiframe for paging
group calculation.
5) T3212 periodic
registration timer.
Cell Option
1) DTXindicator
whether mobile shall
use DTX or not.
2) RADIO-LINK-
TIMEOUT the radio
link timeout for DL
connection that mobile
will use for this cell.
Cell selection parameters
1) CRH : for diff. LAC
2) MS-TXPWR : max
allowed UL power
3) RXLEV-ACCESS-
MIN: min allowed
power in DL to
access
Cell reselection parameters

3. Sys info type
4
(Idle)
Broadcast as similar
information as System
Information Type3 but less
detail.
Sys info type
5
(Dedicated)
BCCH Allocation List
• As same as System
Information Type2 in idle
mode, System Information
Type5 contain the BAList
which mobile have to
monitor in dedicated mode.
• in Type 5 it will send the
list of the same band of the
serving cell, BCCH
allocation list of different
band will be sent in Type
5ter.
• In type 5ter also contain
the information about how
many neighbors from
different band mobiles have
to add in the measurement
report.

4. Sys info type
6
(Dedicated)
Cell options
• PWRC indicated.
• DTX indicator whether
DTX is used.
• Radio Link Timeout The
counter of radio link failure
and release the channel
Radio link timeout work in
following manner, when
MS fail to decode SACCH
block it will decrease by one,
but if the SACCH block can
be decode again its
increment is 2.
Channel
request
Random Access
Information
• Establishment cause
contains the reason for
requesting the establishment
of the connection.
• Random reference
random value as a reference
to the network when channel
is assigned.
Immediate
assignment
Channel Description
• The details of target
physical channel of SDCCH
which MS have to camp on
in dedicated mode.
Request Reference
• Include the Establishment
cause
and random reference value
from
the channel request.
Timing Advance
• The initial timing advance
values,
which BSC calculate from
the delay
of random access

5. Assignment
command
Description ofthe channel
• Channel Type indicate the
target channel
(TCHF/TCHH).
• TN target TCH timeslot
number.
• TSC training sequence
code.
• Hopping RF channel
whether target channel is
HOPPING.
• MAIO start MAI for
hopping.
• HSN hopping sequence
number.
Power Command
• Power level the initial
power use in this connection.
Mobile allocation
• Mobile allocation array the
frequency which will use
when hopping.
Cell channel description
• Channels the frequency
available in this cells
Measurement
report
Serving Cell
measurement
• RxLev Full rxlevel of
serving cell average for full
set.
• Rxlev Sub rxlevel of
serving cell average for sub
set
• RxQual full rxqual of
serving cell average for full
set.
• RxQual Sub rxqual of
serving average for sub set.
Six strongest neighbor
• RxLev rxlevel on BCCH of
neighboring cell .
• BSIC BSIC of the
neighbor.
• BCCH-INDEXthe index
of BCCH on BAList in
system information type5.

6. H.O
Command
Cell Description
• BCCH and BSIC of the
target cell
Channel Description
• allocated channel at target
cell, in case of Hopping it
will inform MAIO and HSN
Handover Reference
• reference value use to
identify the Handover
Access from the mobile
Synchronization
• indicate the handover is
synchronous or
asynchronous. Synchronous
handover case after MS send
Handover Access,it will
tune the transceiver to the
target channel without
waiting for Physical
Information message
H.O Access Handover Reference
• Refer that this Handover
Access belong to which
Handover Command.
Handover Access is a very
short message (1 octet),
which using Access Burst as
same as Channel
Request.
In some case ,it is possible
that this Handover
Access will trigger the
allocation of SDCCH of
surrounding cells because
they think it is the channel
request message.
This phenomena can cause
the problem on immediate
assignment success rate
Physical Info. Timing Advance
• This timing advance tell the
mobile about the timing
advance which will use in
the target cell.

7. Location
Updating
Request
Location Update Type
• Indicate the type of
location update
LocationArea Identity
• the information of current
LAI stored in SIM card (old
LAI).
Mobile Station Classmark
• contain MS capability.
Mobile Identity
• Identity of the MS can be
either TMSI or IMSI
Location
Updating
Accept
Location Area Identity
• the information of new LAI
which will replace the
current LAI in SIM card

10. 3G Layer 3 messages
No. Name Direction Description
1
Measurement
report
UE Node B
The UE sends a report to the Node B
including the best detected neighbors
and their RSCP and Ec/No and the
scrambling code on the UL-DCCH
2
Active set
update
Node B UE
The Node B sends this message to
command the UE to add, remove or
replace the active set as action in the
soft handover process on the DL-DCCH.
It provides the UE with the scrambling
code of the cell exposed to the action
(add, remove or replace) in addition to
the max. UL allowed TX power as a
power control command from the Node
B to the UE (dedicated mode).
3
Active set
update
complete
UE Node B
This message is sent by the UE to the
Node B on the UL-DCCH as an
acknowledgement to the active set
update command received from the
Node B indicating that the action (add,
remove or replace) is completed
successfully.
4
Measurement
control
Node B UE
This is a message sent on the DL-DCCH
by the Node B to the UE in the
dedicated mode to command the UE to
send measurement report on which the
Node B decide what is the SHO
command to be sent
5 Disconnect Node B UE
This message is an indication for
disconnecting the call.
6 Release UE Node B
This message is sent to release the
connection between the MS and Node-
B
7
Release
complete
Node B UE
This message is a response message for
the release message.
8
RRC connection
release
Node B UE
This message is to release the RRC
connection and this message. It includes
authentication code and release cause.
9
RRC connection
release
complete
UE Node B
This message confirms that the RRC
connection is released.
10 Cell selection UE Node B
This message identifies the cell to be
serving the UE at start up.

11. 11 Cell reselection UE Node B
This message identifies the cell to be
serving the UE at idle mode.
12
RRC connection
request
UE Node B
This message is sent by the UE on the
UL-CCCH to request initiating RRC
transmission between the Node B and
the UE. The UE sends MCC, MNC, CPICH
Ec/No, establishment cause, location
area code and TMSI.
13
RRC connection
set up
Node B UE
This message is sent by the Node B to
the UE on the DL-CCCH including
information to help the UE to start
transmission and receiving. These
information as channel coding type, CRC
size, SRNC identity, RNTI, power control
information, rate matching attribute,
scrambling code type, scrambling code,
channel mapping information, radio
bearer information, spreading factor,
UTRAN-DRX-Cycle Length Coeff. and
TFCI.
14
RRC connection
set up complete
UE Node B
This message is sent by the UE to the
Node B on the UL-DCCH as an
acknowledgment to the RRC connection
set up message and associated with UE
capabilities and ciphering algorithm
supported
15
Initial direct
transfer
UE Node B
This message is sent on the UL-DCCH
including service description and core
network domain identity to facilitate
routing and initiate the direct transfer
between the CN and the UE and the
RNC and Node B became transparent.
16
Downlink direct
transfer
Node B UE
This message is sent in the DL including
NAS information directed from the CN
to the UE.
17
Uplink direct
transfer
UE Node B
This message is sent in the UL including
NAS information directed from the UE
to the CN.
18 Identity request Node B UE
This message is sent b y the Node B to
the UE requesting the IMEI of the UE
19
Identity
response
UE Node B
This message is sent by the UE to the
Node B including the IMEI of the UE
20
Authentication
request
Node B UE
This message is sent by the Node B to
the UE including the RAND to request

12. authentication of the UE.
21
Authentication
response
UE Node B
This message is sent by the UE to the
Node B including the SRES after
calculating it from the previous RAND
sent by the network to complete the
authentication process.
22
Security mode
command
Node B UE This message is sent on DL-DCCH.
23
Security mode
complete
UE Node B This message is sent on UL-DCCH.
24 Alerting UE Node B
This message is sent in downlink
direction in case of call originating. It is
sent as constant stream of bits. In case
of terminating call it is an uplink
message. In both cases contains the bits
indicating the sound of ringing tone.
25 Call set up UE Node B
These two messages have the setup
duration one of them for MOC and the
other one for MTC.
26 Call established TEMS Indication
27
Connect
acknowledge
UE Node B
This message is an acknowledgment for
connection before and after the call
established message.
28 Connect Node B UE It indicates establishing the call.
29
Location
updating
request
UE Node B
This message is sent for requesting
location updating. It has the following
parameters:
MCC, MNC, LAC (old), TMSI and class-
mark.
30
Location
updating accept
Node B UE
This message that has the following
parameters:
MCC, MNC and LAC (new)
31
TMSI
reallocation
command
Node B UE
This message is sent on the downlink to
command the UE to change the TMSI.
This message is including MCC, MNC,
LAC and TMSI
32
TMSI
reallocation
complete
UE Node B
This message is sent by the UE as an
acknowledge to the Node B confirming
the TMSI reallocation
33
Location area
update
TEMS Indication for Location update
message.
34
RRC connection
abnormal
release
It is an indication from TEMS.

13. 35 Dropped call
For no service dropped call (poor
coverage). It is an indication from TEMS
36 Paging type 1 Node B UE
This message is sent by the Node B to
one mobile in the cell including the
TEMSI of the paged mobile in addition
to the paging cause.
37 Paging response UE Node B
This message is sent by the UE as an
acknowledgment to the paging type 1
message including the UE capabilities
such as: supported ciphering algorithm,
LCS, frequency capabilities and mobile
identity (TMSI).
38
CM service
request
UE Node B
It contains CM service type, user
equipment capabilities as: RF power
capabilities, ciphering algorithm
supported, Frequency Capability, Mobile
identity (TMSI).
39
CM service
accept
Node B UE
It is a message sent by Node B to
acknowledge CM service request
message
40 Call confirmed UE Node B
It is confirmation for call setup. It
contains radio bearer capabilities.
41
Radio bearer
reconfiguration
Node B UE
This message is sent on changing the
service which consequently need
changing the bearer parameters.
42
Radio bearer
reconfiguration
complete
UE Node B
This message is sent on the DCCH to
acknowledge the radio bearer
reconfiguration message.
43
Physical channel
reconfiguration
Node B UE
This message is sent to notify the UE to
enter or leave the compressed mode.
44
Physical channel
reconfiguration
complete
UE Node B
This message is sent on the DCCH to
acknowledge the physical channel
reconfiguration message.
45
Radio bearer
setup
Node B UE
It is transmitted on (DL-DCCH). It
contains Radio Bearer/logical/transport
channel mapping, Channel coding,
Radio Link Control (RLC) parameters,
TTI,
Transport Format Combination Set

14. (TFCS), Spreading Factor (SF),
Scrambling Code, power
Control parameters.
46
Radio bearer
Setup complete
UE Node B
It is transmitted on (UL-DCCH). It is
acknowledge for radio bearer setup.
47 Progress Node B UE
It is
48 Call proceeding Node B UE
It is sent by the MSC to the MS in case
of mobile originating call to inform the
MS that the address information which
the MS has sent to MSC in Setup
message is received and processed.
49 Call attempt
Indication for call attempt from TEMS.
50 Setup UE Node B
It contains the MS capability (speech
versions) and the called mobile number.
51 Call initiation
It is an indication for call initiation from
TEMS.
52
System
information
Node B UE
It is transmitted on (BCCH – BCH) to be
received by all UEs in the cell. It contains
scrambling code and UARFCN of the cell
and information about MIB and SIBs.
53
System
information
message (MIB,
SC=…..) (value
tag)
Node B UE
It is the main controlling block that the
UE needs to locate. It contains either
scheduling information for the SIBs
directly, or scheduling information for
up to two scheduling blocks which
themselves define the scheduling for
the SIBs. The scheduling is done by
defining the number of segments of
each SIB in the SFN, the repetition of
this SIB and the SIB position within the
System Frame Number (SFN) It contains
also MNC, MCC.
54
System
information
message (SIB3,
SC=….) (value
tag)
Node B UE
It contains some parameters UE needs
in cell selection and reselection
operation as: Qrxlevmin, Qqualmin,.....
55
System
information
message (SIB7,
SC=….)(timer)
Node B UE
It contains measurement of uplink
interference for RACH.
56
System
information
message (SIB5,
SC=….) (value
tag)
Node B UE
It contains the configuration parameters
of physical channels of the cell in idle
mode as: S-CCPCHinformation, PRACH
informationandHSDPAcell capability.

15. 57
System
information
message (SIB12,
SC=….) (value
tag)
Node B UE
It contains the parameters used in intra-
frequency, inter-frequency and inter-
system handovers. It is sent when the
mobile is in Cell_FACH, Cell_PCH,
URA_PCH, Idle mode.
58
System
information
message (SIB1,
SC=….) (value
tag)
Node B UE
It contains core network information as:
LAC, RAC, DRX cycle length coefficient
for both CS and PS and contains the
timers used in events timing which is
important in end to end connection to
avoid unnecessary allocation of network
resources.
59
System
information
message (SIB11,
SC=….) (value
tag)
Node B UE
It contains the neighbors list of the
serving cell and all the parameters for
each neighbor used in intra-frequency,
inter-frequency and inter-system
handovers.
60
Inter-frequency
cell reselection
This message is sent when frequency
changes. It includes the new cell
scrambling code and the UARFCN.